The Lakota are the western division of the Oceti Sakowin, the Seven Council Fires, who moved onto the northern plains in the eighteenth century and became the dominant power there. Their territory was recognised by the Fort Laramie treaty of 1868, which included the Black Hills, the country their accounts hold as the centre.
Gold was found there in 1874 and the United States took the Hills. In United States v. Sioux Nation of Indians the Supreme Court held in 1980 that the taking had been unlawful and awarded compensation. The award has never been accepted. It sits in trust accruing interest, because taking the money would confirm a sale, and the atlas records that refusal as a religious act and not merely a legal one.
The Ghost Dance reached the Lakota in 1890 through the teaching of the Paiute prophet Wovoka, and James Mooney's contemporary study remains the principal account of how it spread and of how differently it was understood in each nation that received it. Alarm at the dance among agents and soldiers ended at Wounded Knee in December 1890 with the killing of some three hundred people, most of them unarmed. Ceremonies including the sun dance were then suppressed by federal policy for decades, and were not clearly protected until the American Indian Religious Freedom Act of 1978.